Conclusion Grading Chart (2010 DGAC)

The 2010 Dietary Guideline Advisory Committee approved the use of the following predefined criteria to grade the strength of the evidence supporting each conclusion statement. These criteria guided members to carefully evaluate the:

quality of studies (both strength of design and execution),

quantity of studies and subjects,

consistency of findings across studies,

the magnitude of effect,

generalizability of findings

reported in the body of literature supporting each conclusion. The chart below was used by the 2010 Dietary Guidelines Advisory Committee and defines the criteria used to determine each grade.

DGAC Conclusion Grading Chart used to evaluate the strength of the body of evidence supporting conclusion statements

Elements

Strong

Moderate

Limited

Expert Opinion Only

Grade Not Assignable

Quality

·Scientific rigor and validity

·Studydesign and execution

Studies of strong design

Free from design flaws, bias, and execution problems

Studies of strong design with minor methodological concerns

OR only studies of weaker study design for question

Studies of weak design for answering the question OR inconclusive findings due to design flaws, bias, or execution problems

No studies available

Conclusion based on usual practice, expert consensus, clinical experience, opinion, or extrapolation from basic research

No evidence that pertains to question being addressed

Consistency

·Consistency of findings across studies

Findings generally consistent in direction and size of effect or degree of association, and statistical significance with minor very exceptions